The exchange occurred at the end of a discussion about former DNC chair Donna Brazile's conclusion that the Clinton campaign had control over the DNC and that the "system" was rigged "to throw the primary to Hillary."

"This is a real problem," Warren said. "But what we've got to do as Democrats now, is we've got to hold this party accountable."

Warren said the moment is a test of DNC Chair Tom Perez's leadership.

"And either he's going to succeed by bringing Bernie Sanders and Bernie Sanders representatives into this process and they're going to say, 'It's fair, it works, we all believe it.' Or, he's going to fail, and I very much hope he succeeds," Warren said. "I hope for Democrats everywhere, I hope for Bernie and for all of Bernie's supporters that he's going to succeed."

Warren joins fellow Senate Democrats for a news conference in front of the Supreme Court on March 17, 2016, calling for Obama's Supreme Court nominee, Merrick Garland, to receive a confirmation hearing and a vote on the floor of the Senate.
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Warren joins Sens. Dianne Feinstein and Kirsten Gillibrand, along with fellow female Democratic senators, for a news conference to announce their support for raising the minimum wage to $10.10 on Capitol Hill on Jan. 30, 2014.
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Warren watches as President Obama shakes hands with Richard Cordray before announcing the nomination of Cordray as head of the Consumer Financial Protection Bureau on July 18, 2011. Despite Warren's role in the creation of the CFPB, Obama ultimately did not appoint her to lead the agency.
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Warren attends a March 4, 2010, hearing of the congressional oversight panel created to oversee the Troubled Asset Relief Program. Her experience on that panel led to her role in the creation of the Consumer Financial Protection Bureau.
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Warren was a law professor at a number of universities in the '70s, '80s and '90s, including Harvard. She became an expert on bankruptcy law and was appointed to the National Bankruptcy Review Commission during the Clinton administration.
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